- A
Man-in-the-middle attack
Why wrong: A man-in-the-middle attack involves intercepting communications between two parties, not sending a flood of SYN packets.
- B
SYN flood attack
A SYN flood attack is characterized by sending numerous SYN packets without completing the handshake, overwhelming the victim's connection table. The internal server is likely compromised and acting as the attacker.
- C
DDoS amplification attack
Why wrong: Amplification attacks use small queries that generate large responses (e.g., NTP, DNS). Sending raw SYN packets is not an amplification technique.
- D
Smurf attack
Why wrong: A Smurf attack involves sending ICMP echo requests to a network broadcast address with a spoofed source IP, causing many replies to flood the victim. This scenario describes TCP SYN packets, not ICMP.
N10-009 Network Security Practice Question
This N10-009 practice question tests your understanding of network security. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A security analyst observes that an internal server is sending a large volume of TCP SYN packets to various external IP addresses, but never completing the three-way handshake. This behavior is indicative of which type of attack?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue:
"never"Why it matters: Absolute qualifier. True only if the statement has zero exceptions — be cautious of options that seem obvious but break down in edge cases.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
SYN flood attack
The correct answer is B. A SYN flood attack occurs when an attacker sends a high volume of TCP SYN packets to a target but never completes the three-way handshake by sending the final ACK. This leaves the target's connection table half-open, consuming resources and potentially exhausting its ability to accept legitimate connections. The observed behavior—internal server sending many SYN packets without completing the handshake—matches the classic signature of a SYN flood, though typically the attacker spoofs the source IP to avoid response traffic.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Man-in-the-middle attack
Why it's wrong here
A man-in-the-middle attack involves intercepting communications between two parties, not sending a flood of SYN packets.
When this WOULD be correct
This would be correct in a scenario where an attacker intercepts and relays messages between two hosts who believe they are directly communicating, such as when an attacker uses ARP spoofing to intercept traffic on a local network.
- ✓
SYN flood attack
Why this is correct
A SYN flood attack is characterized by sending numerous SYN packets without completing the handshake, overwhelming the victim's connection table. The internal server is likely compromised and acting as the attacker.
Clue confirmation
The clue word "never" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
DDoS amplification attack
Why it's wrong here
Amplification attacks use small queries that generate large responses (e.g., NTP, DNS). Sending raw SYN packets is not an amplification technique.
When this WOULD be correct
This option would be correct in a scenario where an attacker sends small requests (e.g., DNS or NTP queries) with a spoofed victim IP to a server, and the server responds with much larger replies to the victim, overwhelming it. For example, 'A server receives a small DNS query from a spoofed IP and sends a large DNS response to that IP, causing network congestion.'
- ✗
Smurf attack
Why it's wrong here
A Smurf attack involves sending ICMP echo requests to a network broadcast address with a spoofed source IP, causing many replies to flood the victim. This scenario describes TCP SYN packets, not ICMP.
When this WOULD be correct
A Smurf attack would be correct if the question described an attacker sending ICMP echo requests to a network broadcast address with a spoofed source IP, resulting in a flood of ICMP replies overwhelming the victim.
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The N10-009 exam frequently reuses these exact scenarios with slightly different constraints.
✓SYN flood attackCorrect answer▾
Why this is correct
A SYN flood attack is characterized by sending numerous SYN packets without completing the handshake, overwhelming the victim's connection table. The internal server is likely compromised and acting as the attacker.
✗Man-in-the-middle attackWrong answer — click to see why▾
Why this is wrong here
A man-in-the-middle attack involves intercepting and potentially altering communications between two parties, not sending a large volume of SYN packets without completing the handshake.
★ When this WOULD be the correct answer
This would be correct in a scenario where an attacker intercepts and relays messages between two hosts who believe they are directly communicating, such as when an attacker uses ARP spoofing to intercept traffic on a local network.
Why candidates choose this
Candidates may confuse the concept of an attacker intercepting traffic with the idea of the server sending packets to external IPs, mistakenly thinking the server is acting as a middleman.
✗DDoS amplification attackWrong answer — click to see why▾
Why this is wrong here
A DDoS amplification attack involves sending small queries to a server with a spoofed source IP, causing the server to send large responses to the victim. The question describes the internal server sending SYN packets, not receiving amplified responses, so this does not match.
★ When this WOULD be the correct answer
This option would be correct in a scenario where an attacker sends small requests (e.g., DNS or NTP queries) with a spoofed victim IP to a server, and the server responds with much larger replies to the victim, overwhelming it. For example, 'A server receives a small DNS query from a spoofed IP and sends a large DNS response to that IP, causing network congestion.'
Why candidates choose this
Candidates may confuse the high volume of traffic in a SYN flood with the amplification effect in DDoS amplification attacks, especially since both involve flooding. They might think the internal server is being used to amplify traffic to external targets.
✗Smurf attackWrong answer — click to see why▾
Why this is wrong here
A Smurf attack involves sending ICMP echo requests with a spoofed source IP to a network's broadcast address, causing all hosts to reply to the victim. The question describes TCP SYN packets, not ICMP, and the server is the source, not the target of amplification.
★ When this WOULD be the correct answer
A Smurf attack would be correct if the question described an attacker sending ICMP echo requests to a network broadcast address with a spoofed source IP, resulting in a flood of ICMP replies overwhelming the victim.
Why candidates choose this
Candidates may confuse amplification attacks (like Smurf) with SYN floods because both involve high volumes of traffic and denial of service, but they differ in protocol and mechanism.
Analysis generated from the official N10-009blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Common exam traps
Common exam trap: answer the scenario, not the keyword
CompTIA often tests the distinction between a SYN flood (which uses TCP SYN packets and incomplete handshakes) and a DDoS amplification attack (which uses UDP or other protocols with spoofed sources), so candidates mistakenly choose amplification when they see 'large volume' and 'external IPs' without recognizing the TCP SYN signature.
Trap categories for this question
Scenario analysis trap
A Smurf attack involves sending ICMP echo requests to a network broadcast address with a spoofed source IP, causing many replies to flood the victim. This scenario describes TCP SYN packets, not ICMP.
Detailed technical explanation
How to think about this question
Under the hood, a SYN flood exploits the TCP three-way handshake: the server allocates memory in a Transmission Control Block (TCB) upon receiving a SYN and sends a SYN-ACK, then waits for the final ACK. With a backlog queue (e.g., net.core.somaxconn default 128 or 4096), the server can only hold a limited number of half-open connections. Attackers often spoof the source IP to prevent the server from receiving RST packets from non-existent hosts, and modern defenses include SYN cookies (RFC 4987) that encode connection state in the SYN-ACK sequence number, avoiding resource allocation until the handshake completes.
KKey Concepts to Remember
- Read the scenario before looking for a memorised answer.
- Find the constraint that changes the correct option.
- Eliminate answers that are true in general but not in this case.
TExam Day Tips
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A practitioner preparing for the N10-009 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
Visual reference
Quick reference
IPv4 Address Class Summary
| Class | First Octet Range | Default Mask | Networks | Hosts per Network |
|---|---|---|---|---|
| A | 1–126 | /8 (255.0.0.0) | 126 | 16,777,214 |
| B | 128–191 | /16 (255.255.0.0) | 16,384 | 65,534 |
| C | 192–223 | /24 (255.255.255.0) | 2,097,152 | 254 |
| D | 224–239 | N/A | Multicast groups | — |
| E | 240–255 | N/A | Reserved / experimental | — |
127.x.x.x is reserved for loopback. Modern networks use CIDR (classless) rather than classful addressing.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
- →
Network Security — study guide chapter
Learn the concepts, then practise the questions
- →
Network Security practice questions
Targeted practice on this topic area only
- →
All N10-009 questions
520 questions across all exam domains
- →
CompTIA Network+ N10-009 study guide
Full concept coverage aligned to exam objectives
- →
N10-009 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related N10-009 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Networking Concepts practice questions
Practise N10-009 questions linked to Networking Concepts.
Network Implementation practice questions
Practise N10-009 questions linked to Network Implementation.
Network Operations practice questions
Practise N10-009 questions linked to Network Operations.
Network Security practice questions
Practise N10-009 questions linked to Network Security.
Network Troubleshooting practice questions
Practise N10-009 questions linked to Network Troubleshooting.
Network+ network fundamentals practice questions
Practise N10-009 questions linked to Network+ network fundamentals.
Practice this exam
Start a free N10-009 practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this N10-009 question test?
Network Security — This question tests Network Security — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: SYN flood attack — The correct answer is B. A SYN flood attack occurs when an attacker sends a high volume of TCP SYN packets to a target but never completes the three-way handshake by sending the final ACK. This leaves the target's connection table half-open, consuming resources and potentially exhausting its ability to accept legitimate connections. The observed behavior—internal server sending many SYN packets without completing the handshake—matches the classic signature of a SYN flood, though typically the attacker spoofs the source IP to avoid response traffic.
What should I do if I get this N10-009 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Are there clue words in this question I should notice?
Yes — watch for: "never". Absolute qualifier. True only if the statement has zero exceptions — be cautious of options that seem obvious but break down in edge cases.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Keep practising
More N10-009 practice questions
- Which of the following network devices operates primarily at Layer 2 of the OSI model and uses MAC addresses to forward…
- Which of the following is a characteristic of UDP when compared to TCP?
- Which of the following IPv6 addresses is a valid link-local address?
- Which of the following security mechanisms requires a user to authenticate before gaining access to the wired network at…
- Which of the following network protocols operates at the Transport layer of the OSI model and provides connection-orient…
- Which of the following is a characteristic of a connectionless protocol at the transport layer?
Last reviewed: Jun 30, 2026
This N10-009 practice question is part of Courseiva's free CompTIA certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the N10-009 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.